Cosmetic applicator for applying a cosmetic composition to keratinous fibers such as eyelashes or eyebrows

ABSTRACT

A cosmetic applicator (3) for applying a composition (P) to human keratinous fibers, notably eyelashes or eyebrows, is provided. The cosmetic applicator (3) comprises: —A stem (5) having at least a rectilinear portion extending along a rectilinear axis (Y), —a brush (10) at one end of the stem (5), the brush comprising: —a curved core (43) having a distal end (46) and defining a convex side and an opposite concave side, the distal end of the core being offset from the rectilinear axis (Y) of the stem on the convex side of the core, —application members (41) supported by the core (43).

FIELD OF THE INVENTION

The present invention relates to brushes for applying a cosmeticcomposition to the eyelashes or eyebrows, notably a makeup or careproduct, for example mascara, and to packaging and application devicescomprising such a brush.

PRIOR ART AND OBJECTIVES OF THE INVENTION

Mascara applicators, in which the brush comprises a core formed by twoarms of a metal wire that are twisted together and grip bristles, areknown. Since the bristles used are generally of the same length, oncethe arms are twisted, the brush has an envelope surface in the form of acylinder of revolution. Such a shape has limited effectiveness in termsof loading the eyelashes with product and in terms of separation.

Efforts have thus been made to give the envelope surface more complexshapes so as to form on the brush, after wiping, zones that are moreheavily laden with product, making it possible to properly load theeyelashes, and zones that are less heavily laden or are laden little,these being usable to comb and separate the eyelashes. Finding the shapethat results in the optimum makeup result requires numerous tests, sincemany factors are involved.

Similar issues arise with brushes made by injection molding.

EP1236419 discloses brushes with a curved core and a distal end of thecore offset from the longitudinal axis of the stem, on the concave sideof the core.

There is a need to make it easier to apply makeup along the upper andlower rows of the eyelashes.

There is also a need to improve brushes, notably to benefit from brushesthat are capable of satisfactorily making up the eyelashes or eyebrows,by providing a satisfactory load of product and good combing ability.

Applicator

The present invention, according to one of its aspects, relates to anapplicator for applying a cosmetic composition to human keratinousfibers, notably eyelashes or eyebrows, comprising:

-   -   A stem having at least a rectilinear portion extending along a        rectilinear axis,    -   a brush at one end of the stem, the brush comprising:        -   a curved core having a distal end and defining a convex side            and an opposite concave side, the distal end of the core            being offset from the rectilinear axis of the stem on the            convex side of the core,        -   application members supported by the core.            “Convex” means convex toward the outside. By “the distal end            of the core being offset from the rectilinear axis of the            stem on the convex side of the core” it is meant that the            vector GD defined by the orthogonal projection G of the            distal end of the core onto the rectilinear axis of the stem            and the distal end D of the core and oriented from G to D            has a substantially same orientation as a vector H            perpendicular to the rectilinear axis of the stem and            oriented from the concave side of the longitudinal axis of            the core toward the convex side. In other words, if one has            to tilt the core from an initial configuration where the            distal end would be aligned with the rectilinear            longitudinal axis of the stem to a final configuration            having the desired offset, the tilting would be carried out            by deforming the core in a direction going from the intrados            of the core toward the extrados of the core.            Thanks to the invention, the performance of the brush in            terms of loading the lashes with product while providing            satisfactory combing is increased. By virtue of the            invention, a brush is available that offers a reserve of            product, in the concave portion, and a combing zone, less            heavily laden with product, in the convex portion. Due to            the offset, there can be more interference between the wiper            member and the brush, leading to less composition left on            the convex side of the brush near the distal end thereof.            This increased interference may allow to use more viscous            compositions, with increased make-up performance. The            invention may make it easier to apply the composition, and            to avoid formation of clumps during application. The            invention makes it also easier to make up lashes in the            corner of the eye.            Preferably, the stem is rectilinear along its entire length.            This enables to use a conventional straight stem for the            applicator, easy to manufacture and assemble with the brush.            In some variants, however, the stem has a main rectilinear            portion, that extends preferably over most of its length,            and a distal portion that makes an angle with the            rectilinear portion of the stem, the orientation of the            distal portion of the stem providing, or at least            contributing to some extent, to the desired offset for the            distal end of the core.            Preferably, the core is a twisted wire core, but the            invention also applies to injection molded brushes. In case            the core is a twisted wire core, the application members are            bristles held between the turns of the strands of the core            that are twisted together, as is conventional.            Preferably, the core is non rectilinear over its entire            length from the stem to its distal end. However, in some            variant embodiments, the core may have at least one segment            that is rectilinear, while keeping an overall curved shape.            Preferably, the curved core is of constant curvature, but            the core may have a radius of curvature that varies along            the bristle carrying portion.            The distance from the rectilinear axis of the stem to the            curved core may reach a maximum at some position between the            proximal and distal ends of the curved core, preferably at            some position between one quarter and three quarters of the            length of the curved core between these proximal and distal            ends, more preferably between one third and two thirds of            said length.            Preferably, the core extends along a longitudinal axis of            substantially constant radius of curvature from the stem to            the distal end of the core. Such a radius of curvature may            be greater or equal to 34 mm and less or equal to 47 mm,            being preferably of about 40 mm            Preferably, the longitudinal axis of the core extends in a            plane. Such a plane is preferably a midplane plane of            symmetry for the envelope surface of the brush defined by            the free ends of the application members.            Preferably, the application members define an envelope            surface of non-circular cross section along at least part of            its length. The application members can be bristles or            spikes that extend around the core.            The envelope surface may define at least one facet of flat            cross section on the convex side of the core, i.e. on the            extrados of the brush. In some variants, the envelope            surface defines at least one facet of recessed cross section            on the convex side of the core. Such a recessed cross            section may form at least one longitudinal groove extending            along the brush on the convex side of the core, i.e. on the            extrados of the brush.            In some embodiments, the cross section of the surface            envelope of the brush has a plurality of rectilinear            segments connected by circular arcs. The angular extension            of the circular arcs around the core may be relatively            small, giving the cross section of the brush a substantially            triangular shape.            The cross section of the surface envelope may be of            substantially triangular contour, with an apex situated in            the plane along which the longitudinal axis of the core            extends.            The tilt angle between the rectilinear axis of the            rectilinear portion of the stem and a straight line            connecting the distal end of the core to the distal end of            the rectilinear portion of the stem preferably ranges from            0.5 to 10°, better 0.6 to 8°, more preferably from 0.7° to            5.7° and most preferably from 2° to 4.5°, being for example            of about 3.2°.            Preferably, the offset is greater than 0.5 mm. Preferably            the offset is no greater than 2.5 mm. It is advantageous            that the offset remains small enough to allow the            introduction of the brush in a container containing the            composition to be applied and provided with a wiper member            defining a wiping orifice, without the distal end of the            core abutting against the wiper member, with an introduction            movement of the brush being a linear displacement along the            rectilinear axis of the stem. This enables an automated            mounting of the applicator on the container with a simple            mechanism. The offset may not be greater than half the            diameter of the wiping orifice, and preferably is close to            it. The offset f may range from 0.8D/2 to 1.2D/2, better            from 0.9D/2 to 1.1D/2, even better from 0.8D/2 to D/2 or            more preferably from 0.9D/2 to D/2, if D is the diameter of            the wiping orifice.

The envelope surface may comprise a frustoconical or ogee-shaped distalportion with a cross section that becomes smaller toward the distal endof the core. The frustoconical or ogee-shaped distal portion may extendover a length greater than one quarter of the length L of the portion ofthe core bearing the application members, and less than one third of thelength L of the portion of the core bearing the bristles.

At its opposite end from the brush, the stem may be fastened to a capfor closing a container.

Device

According to another of its aspects, in combination with the above, theinvention further relates to a device for applying a cosmeticcomposition on keratinous fibers, preferably eyelashes, comprising:

-   -   A container containing said composition, comprising a wiper        member and,    -   an applicator according to the invention, as defined above.        The wiping member is configured for removing the excess product        present on the stem and on the brush. This wiping member        comprises, for example, a lip made of an elastomer material,        defining a wiping orifice which preferably has a circular cross        section, the diameter of which corresponds substantially to that        of the stem.        The wiper member and the brush may be configured so that when        the applicator is withdrawn from the container along said        rectilinear axis, application members situated on the convex        side of the core, i.e. on the extrados of the brush, at an axial        position less than 3 mm from the proximal end of the brush,        measured along the curved longitudinal axis of the core, contact        the wiper member. In some embodiments, the smaller this        distance, the better it is, as this means that the extrados of        the brush contacts the wiper member at an earlier stage of the        passage of the brush through the wiper member, resulting in the        absence of clump of composition near the proximal end of the        brush on the extrados thereof.

Method for Manufacturing a Brush

According to another of its aspects, in combination with the above, thepresent invention further relates to a method for manufacturing a brushfor use in an applicator as defined above, comprising:

-   -   Machining a twisted wire core brush with a rectilinear core to        form at least one planar or recessed facet of an envelope        surface defined by the free ends of the bristles, the core        having a proximal portion for fixing into a stem and a bristle        carrying portion,    -   deforming the core to impart to the bristle carrying portion a        curved shape with a convex side and a concave side, the distal        end of the core being offset from the longitudinal axis of the        proximal portion of the core on the convex side.        The core may be deformed along a plane of curvature.        The planar or recessed facet preferably lies on the extrados of        the brush after curvature of the core.        The machining may comprise forming at least one planar facet or        at least one facet with a recess of the envelope surface, along        the longitudinal direction of the brush, over most of its        length.        The machining may comprise forming three planar facets of the        envelope surface, giving the envelope surface a substantially        triangular shape in cross section, an apex lying in the plane of        curvature of the core.        The machining may comprise forming a frustoconical head.        The one or more facets may be machined so that they intersect        the frustoconical head.        The deforming of the core may comprise imparting the bristle        carrying portion a constant curvature then tilting the core at        the junction of the bristle carrying portion with the proximal        portion, or vice versa.        According to another of its aspects, the present invention        further relates to a method for manufacturing a brush for use in        an applicator as defined above, comprising injection molding the        core and the application members in at least one plastics        material.

Makeup Method

A further aspect of the invention is a makeup method for making up humankeratinous fibers, comprising applying a cosmetic composition to saidfibers using an applicator as defined above. In such method, the brushaccording to the invention is loaded with the cosmetic composition andthen the composition is applied to the surface to be made up, notablythe eyelashes or the eyebrows. During the movement of the brush throughthe wiper member, the brush may follow a translational movement alongthe rectilinear axis of the stem. The brush may be used to make up thelashes at the corner of the eye, using a portion of the brush on theextrados near the distal end of the core. Such portion may carry alittle quantity of composition due to the interference of the brush withthe wiping member, and thus be useful for combing said lashes at thecorner of the eye.

DETAILED DESCRIPTION

The invention may be understood better from reading the followingdetailed description of nonlimiting exemplary embodiments thereof andfrom studying the appended drawing, in which:

FIG. 1 shows, in schematic longitudinal section, one example of acosmetic device according to the invention,

FIG. 2 is a side view in isolation of the brush of the device of FIG. 1,

FIG. 3 is a front view of the brush along arrow III of FIG. 2 ,

FIG. 4 is a perspective view of the brush,

FIG. 5 is a side view of a rough brush from which a brush according tothe invention is made,

FIG. 6 is a front view along arrow VI of FIG. 5 ,

FIG. 7 shows the rough brush after machining,

FIG. 8 is a front view along arrow VIII of FIG. 7 ,

FIG. 9 and FIG. 10 illustrate the wiping of the brush during withdrawalof the applicator,

FIG. 11 to FIG. 14 are cross sections of variant embodiments of thebrush,

FIG. 15 shows an example of stem and core assembly,

FIG. 16 is a similar view to FIG. 16 showing a variant embodiment of thestem and core,

FIG. 17 is a partial longitudinal section of a variant of a brush.

In the following description, identical elements or elements havingidentical functions bear the same reference sign. Their description isnot repeated for each of the FIG.s, only main differences between theembodiments being mentioned.

The cosmetic device 1 shown in FIG. 1 comprises a container 2 containinga cosmetic composition P to be applied to the eyelashes or the eyebrowsand an applicator 3 which may, in the example in question, be fixedremovably to the container 2. The composition P comprises, for example,one or more pigments, notably an iron oxide. It is for example amascara.

The applicator 3 comprises a stem 5, of rectilinear longitudinal axis Y,provided at a distal end 7 with a brush 10 according to the inventionand at the other end with a cap 11 for closing the container 2 in asealed manner. The latter has a body which is provided at the top with athreaded neck 14 onto which the cap 11 can be screwed in order to closethe container 2. In an alternative form the applicator can be fixed tothe container in some other way.

The neck 14 may accommodate, as illustrated, a wiping member 20 which isfor example inserted into the neck 14. This wiping member 20 comprises awiper lip 21 that defines a wiping orifice having a diameter D adaptedto that of the stem 5, for example a diameter of 4.25 mm.

The brush 10 may be fixed, in a conventional manner, in a seat 8(visible in FIG. 15 ) provided at the distal portion 6 of the stem 5,which is advantageously made of a thermoplastic material.

The brush 10 comprises a twisted metal core 40 comprising a curvedportion 43 bearing bristles 41 and a rectilinear proximal portion 44,visible in FIG. 2 , that is inserted into the above-mentioned seat 8provided at the distal portion 6 of the stem 5. The core 40 may be madeby twisting together two strands of a U-shaped metal wire, the bristlesbeing clamped by the turns of the wire. The diameter of the metal wiremay vary and is for example of about 0.7 mm.

The free end of the bristles 41 define an envelope surface E with ashape that results from the trimming of the bristles 41 and thecurvature imparted to the core 40 after trimming as will be describedbelow.

The bristles 41 may be of any kind, with a circular cross section orbetter a non-circular cross section, for example a C-shaped crosssection.

The bristles may be made of any material, preferably a thermoplasticmaterial such as polyamide.

The outside diameter of the bristles may vary and for example is about13/100 mm.

To manufacture the brush 10, one may start from the rough brush shown inFIG. 5 , having a straight core and an envelope surface with acylindrical portion E1 and a frustoconical head portion E2. The overalllength L of the bristle carrying portion may range from 20 to 35 mm,being for example of about 28 mm, while the length/of the frustoconicalportion E2 may be of about 9 mm. The diameter d2 at the distal end ofthe frustoconical portion may be of about 4 mm, and the diameter d1 ofthe cylindrical portion of circular cross section may be about 7.5 mm,the invention being not limited to any specific value.

Then the bristles are trimmed to form three planar facets 51, 52 and 53as shown in FIG. 7 and FIG. 8 .

Each of these facets extends over the whole length of the cylindricalportion E1 and a part of the frustoconical head portion E2, as one cansee on FIG. 7 .

The angle h between the facets 51 and 52 may be about 60°, as shown inFIG. 8 , giving the cross section of the brush an overall triangularcontour.

The facets 51, 52 and 53 are separated by circular arcs 55 in crosssection.

Once the brush is trimmed, the bristle carrying portion 43 of the coreis permanently deformed to impart the brush its final shape. The planarfacets 51, 52 and 53 are deformed into facets 151, 152 and 153 ofarcuate shape, respectively, the facet 153 extending along the extradosof the brush.

In the example shown, the radius of curvature R of the longitudinal axisX of the curved core portion 43 is constant and of about 40 mm. Thelongitudinal axis X of the curved portion 43 extends in a midplane M ofthe envelope surface E, that is a plane of symmetry.

The curved portion 43 has a convex side, that is left to the core inFIG. 2 and adjacent the extrados of the brush, and a concave side, thatis right to the core in FIG. 2 .

According to the invention, the distal end 46 of the core 40 is offsetfrom the longitudinal axis Y of the stem 5 by a non-zero distance f, thedistal end 46 being offset on the convex side, i.e. being to the left ofthe longitudinal axis Y in FIG. 2 as is the extrados of the brush.

The angle w between on the one hand the straight line Z joining the corewhere it connect the distal end of the stem, that coincidessubstantially with the junction of the portions 43 and 44 of the core40, and the distal end 46 of the core 40, and on the other end thelongitudinal axis Y, is about 3.2° is the example shown.

Thanks to the offset of the distal end 46 of the core relative to thelongitudinal axis of the stem 5, the wiping occurs more efficiently onthe extrados of the brush, as will be explained further with referenceto FIG. 9 and FIG. 10 .

FIG. 9 shows the brush 10 when it reaches the wiper lip 21 duringwithdrawal of the applicator from the container.

As one can see, the bristles of the facet 153 that first contact thewiper lip 21 have an abscissa x, measured along the longitudinal axis Xof the curved portion 43 from the proximal end of origin x₀, that isrelatively small, for example 3 mm or less.

Such a contact at an early stage of the withdrawal ensures that thefacet 153 is wiped efficiently along almost all its length.

When the brush has almost entirely passed the wiper lip 21, as shown inFIG. 10 , the edge of the wiping lip comes relatively close to thecurved portion of the core in the area A of the extrados near the distalend of the brush, thus providing strong wiping action in this area A.

The offset f is preferably however small enough so that when theapplicator 3 is mounted on the container 2 with a displacement of theapplicator 3 along the longitudinal axis Y, the distal end of the coreengages in the wiping orifice without abutting against the wiper lip 21.This facilitates an automated mounting of the applicator 3 on thecontainer 2.

In variant embodiments, the brush has other shapes in cross section.

For example, as shown in FIG. 11 , the brush may exhibit only one facet153 on the envelope surface, on the extrados of the brush.

The facet 153 may be flat in cross section, as shown in FIG. 11 , orrecessed, as exemplified in FIG. 12 to FIG. 14 .

In FIG. 12 , the facet 153 has a C-shape in cross section, in FIG. 13 aV-shape and in FIG. 14 a U-shape, but other forms of longitudinalnotches are possible.

The offset of the distal end of the core according to the invention mayallow the wiping of the bottom of the notch at least near in an areaclose to the distal end of the brush, thus leading to a wiped brushhaving a portion on its extrados with less composition left on it,better adapted to comb the lashes.

In the variant illustrated in FIG. 16 , the stem 5 has a rectilinearmain portion 5 a that extends to the cap 11 and a relatively shortrectilinear distal portion 5 b that extends along an axis K that makesan angle g with the axis Y of the main portion 5 a.

The core 40 is fixed in a seat 8 provided in the distal portion 5 b,with the curved portion 43 extending in a same plane as the planedefined by the axes Y and K. The convex side of the curved core 43 isoriented toward the left in FIG. 16 , as is the axis K below the mainportion 5 a.

In the embodiment of FIG. 15 , the core 40 is angled right where itleaves the stem 5 to help provide the desired offset of the distal endof the core. In the embodiment of FIG. 16 , thanks to the angled distalportion 5 b of the stem, the core 40 may not need to be angled where itleaves the stem, as shown.

The invention also applies to injection molded brushes.

FIG. 17 shows an example of a brush 10 made by injection molding of oneor more plastics material, such as thermoplastics elastomers, withapplication members 41 such as spikes made integrally with the core 40,in the same or in a different material.

The invention is not limited to the illustrative embodiments that havejust been described, the features of which may be combined with oneanother within alternative forms that are not illustrated.

1. A cosmetic applicator for applying a composition to human keratinousfibers, notably eyelashes or eyebrows, comprising: a stem having atleast a rectilinear portion extending along a rectilinear axis, a brushat one end of the stem, the brush comprising: a curved core having adistal end and defining a convex side and an opposite concave side, thedistal end of the core being offset from the rectilinear axis of thestem on the convex side of the core, application members supported bythe core.
 2. The applicator of claim 1, the stem being rectilinear alongits entire length.
 3. The applicator of claim 1, the core being atwisted wire core.
 4. The applicator of claim 1, the core being nonrectilinear over its entire length from the stem to its distal end. 5.The applicator of claim 4, the core extending along a longitudinal axisof substantially constant radius of curvature from the stem to thedistal end of the core.
 6. The applicator of claim 5, the radius ofcurvature being greater or equal to 34 mm and less or equal to 47 mm. 7.The applicator of claim 1, the longitudinal axis of the core extendingin a plane, preferably a midplane for an envelope surface of the brushdefined by the application members.
 8. The applicator of claim 1, theapplication members defining an envelope surface of non-circular crosssection along at least part of its length.
 9. The applicator of claim 8,the envelope surface defining at least one facet of flat or recessedcross section on the convex side of the core.
 10. The applicator ofclaim 7, the cross section of the envelope surface having a plurality ofrectilinear segments connected by circular arcs.
 11. The applicator ofclaim 8, the cross section being of substantially triangular contour,with an apex preferably situated in a midplane for the envelope surface.12. The applicator of claim 1, the tilt angle between the rectilinearaxis of the rectilinear portion of the stem and a straight line joiningthe distal end of the core to the distal end of the rectilinear portionof the stem ranging from 0.5 to 10°, better 0.6 to 8°, preferably from0.7° to 5.7° and more preferably from 2° to 4.5°.
 13. The applicator ofclaim 1, the offset being not less than 0.5 mm and no greater than 2.5mm.
 14. The applicator according to claim 1, the application membersbeing bristles or spikes that extend around the core.
 15. A device forapplying a cosmetic composition on keratinous fibers, comprising: acontainer containing said composition, comprising a wiper member and, anapplicator as defined in claim
 1. 16. The device of claim 15, the wipermember and the brush being configured so that when the applicator iswithdrawn from the container along said rectilinear axis, applicationmembers situated on the convex side of the core, at an axial positionless than 3 mm along the longitudinal axis of the core from the proximalend of the bristle portion of the brush, first contact the wiper member.17. A method for manufacturing a brush for use in an applicator asdefined in claim 1, comprising: machining a twisted wire core brush witha rectilinear core to form at least one planar or recessed face of anenvelope surface defined by the free ends of the bristles, the corehaving a proximal portion for fixing into a stem and a bristle carryingportion, deforming the core to impart to the bristle carrying portion acurved shape with a convex side and a concave side, the distal end ofthe core being offset from the longitudinal axis of the proximal portionon the convex side of the core.
 18. The method of claim 17, the corebeing deformed along a plane of curvature, the machining comprisingforming three planar facets of the envelope surface, giving the envelopesurface a substantially triangular shape in cross section, an apex lyingin the plane of curvature of the core.
 19. The method of claim 17, themachining comprising forming a frustoconical head portion.
 20. Themethod of claim 18, the planar facets intersecting the frustoconicalhead portion.
 21. The method according to claim 17, the deforming of thecore comprising imparting the bristle carrying portion a constantcurvature then tilting the core at the junction of the bristle carryingportion with the proximal portion, or vice versa.
 22. A method formanufacturing a brush for use in an applicator as defined in claim 1,comprising injection molding the core and the application members in atleast one plastics material.
 23. A method for making up human keratinousfibers, comprising applying a cosmetic composition to said fibers usingan applicator as defined in claim 1.